Nonequilibrium ionization of nitrogen: The role of stepwise ionization from metastable states in the presence of superelastic electronic collisions

Abstract

Electron impact ionization rate coefficients involving N2 metastable electronic states have been calculated in discharge and postdischarge conditions by using the electron energy distribution functions which take into account both the presence of superelastic electronic (SEC) and vibrational (SVC) collisions [J. Appl. Phys. 59, 4004 (1986)]. The results show that stepwise ionization from metastable states can overcome the corresponding rates from the ground state especially in the absence of SVC. Finally, a comparison of the present results with those coming from associative ionization involving metastable electronic and vibrational states is presented and discussed.